The Tensions had begun in the past century between the four main Colonial powers in Europe, the United Kingdom of Britain and North America, New France (Albany Congress), the Ottoman Empire and the German Colonial Empire.
It began when New France demanded that Britain give back the French Provinces ceded during the Napoleonic Wars. The British refused to and a war was almost called, and there hadn't been a major war between the two Empires in years. But this was avoided due to German intervention saying that "it was Napoleons fault it was lost, if the French want the provinces back they should take their quarrels up with the man himself."
Due to the Germans standing up for them the British started to forge a better relationship with the Germans. While the French were outraged that the Germans spoke to them in this manner, and so started outrageous demands on them saying they want Alsace-Lorraine back from the "evil Prussians who took it" This has been kept up by the French for a long time and lately it has become more of a violent argument, with terrorism in both Germany and France. Many people have been slaughtered by terrorists on both sides.
Many landmarks had been targeted, for example the Arc De Triomphe in Paris has been hit multiple times by bombs as well as the Brandenburg Gate in Berlin. Due to this both countries have begun to close their countries to each other and so tensions have risen rapidly.
While Germany has secured a Mutual Protection Pact with Britain, France managed to create a pact with the Ottoman Empire by paying over a billion francs.
All four countries have begun to prepare themselves for the inevitable world war.